According to the company 235 design patents are currently infringed upon by the open source operating system and its related programmes. 107 of these, it claims, come from the OS's interface alone.

"This is not a case of some accidental, unknowing infringement," said Microsoft Licensing Chief Horatio Gutierrez. "There is an overwhelming number of patents being infringed."

Of course this is not the first time Microsoft has chased a Linux vendor as it agreed a royalties deal with Adobe last year in return for dropping potential patent action. Dell has since agreed a similar contract which may safeguard Ubuntu. Still, Linux as a whole has seen this coming and the Open Invention Network has been set up specifically to safeguard the numerous Linux vendors.